Technologies of performing speech recognition and semantic analysis on speeches from users and responding by voice have been conventionally developed. Specifically, it is possible to perform speech recognition processes within a practical time due to recent development in speech recognition algorithms and computer technologies, and user interfaces (UIs) for smartphones or tablets that use voice have become popular.
For example, it is possible to respond, by voice, to a question made by voice of a user, or it is possible to execute a process corresponding to an instruction made by voice of a user, by using an application of a voice UI installed in a smartphone, a tablet terminal, or the like.